An organic light emitting display device is a self-emission display device which has an organic light emitting diode that emits light to display an image. Unlike a liquid crystal display, the organic light emitting display device does not require a separate light source. As such, it is possible to relatively reduce a thickness and a weight thereof, and there are other advantages such as low power consumption, high luminance, and rapid response speed.
The organic light emitting diode display includes a hole injection electrode, an organic emission layer, an electron injection electrode, and a thin film encapsulation layer. In the organic light emitting diode, a hole supplied from the hole injection electrode and an electron supplied from the electron injection electrode are coupled with each other in the organic emission layer to form an exciton, and light is generated by energy generated when the exciton falls to a ground state.
Respective layers included in the organic light emitting display device are made of different materials, and as a result, a difference in the refractive indices between the layers occurs. Total reflection due to the difference in the refractive indices between the layers occurs in the organic light emitting display device, and a part of the light generated in the organic emission layer is restricted due to the internal total reflection and then dissipates.